DESCRIPTION: Applicant's Abstract This application is for support of the 31st annual meeting of the International Narcotics research Conference (INRC). The Conference will be held in Seattle, Washington, July 10-15, 2000. The INRC has for many years been the most prestigious international meeting for the dissemination and exchange of current information in the area of biomedical research on opiate drugs and on the endogenous opioid system. The topics range from molecular to behavioral and clinically related studies. There is increasing discussion of other abused drugs, such as marihuana, cocaine and alcohol, since extensive interaction between these drugs and the endogenous opioid system has been documented. Support is requested primarily for partial travel support to enable young scientists, i.e., graduate students, postdoctoral fellows and young independent researchers, to participate in the Conference. A small portion of the funds will be used to support distinguished plenary speakers from other disciplines, relevant to research on addictive drugs, who will describe strategies, concepts or techniques likely to be useful to an INRC audience. Invited symposium speakers and a very small number of senior scientists, unable to fund their own travel, will receive partial support. Finally, we ask for funds for administrative and meeting expenses, representing about 15% of the total budget. This year we plan to invite 4 plenary speakers covering topics from dimerization of dopamine receptors to co-morbidity of drug abuse and psychiatric illness. There will be 7 symposia covering a wide range of topics described in the application, with only limited overlap with the 1999 Conference, in areas deemed sufficiently fast moving to deserve an update. A number of relevant contributed papers will be presented at each symposium and there will be 3 poster sessions, each lasting 3 hours, at which there is always much exchange and discussion. Ample time is also allotted at the symposia for discussion. Lively discussions are a hallmark of INRC meetings, held in informal settings where interaction between participants is easy.